import java.util.Scanner;

//定义一个int类型变量i,i为由浮点数变量d四舍五入后的整数类型，请将转换后的i进行输出
public class Test2 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        double d = sc.nextDouble();
        double d1 = 12.45;
        int i = 0;
        while(true) {
            if((d=(d * 10)) % 10 >= 5) {
                i = (int) d1 + 1;
                break;
            } else if(d % 10 < 4) {
                i = (int) d1;
               break;
            }
            else {
                if ((d * 10) % 10 == 0) {
                    i = (int) d1;
                    break;
                }else{
                    continue;
                }

            }
        }
        System.out.println(i);
    }
}
